In an automatic vending machine for vending coffee, for example, by percolating coffee from powdered coffee beans, the powdered coffee material would be deteriorated if it is exposed to the atmosphere for a prolonged period of time because of oxidation of the material by oxygen and moisture in the atmosphere, resulting in very poor coffee if prepared.
The inventor of this application disclosed in U.S. patent application Ser. No. 692,151 now U.S. Pat. No. 5,163,356 an apparatus for storing a powder material in a hopper, which hopper is in turn supplied with the powder material when the material becomes scarce in the hopper containing the material by opening a pack. The pack is supplied from a pack storage section of the machine.
With the apparatus mentioned above, powder material preserved in the pack may be kept fresh since it is not exposed to atmosphere, thereby maintaining good quality of the material. However, the apparatus used for opening the pack often leaves part of the material in the pack when the pack is opened. Furthermore, it takes time to unpack the material in the pack, since the apparatus has only a pair of parallel, linear arrays of cutters having regularly spaced-apart edges which may cut the pack only along two parallel lines at the bottom of the pack.